12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091 |
- from django.db.models import Index
-
- __all__ = ['BrinIndex', 'GinIndex', 'GistIndex']
-
-
- class MaxLengthMixin:
- # Allow an index name longer than 30 characters since the suffix is 4
- # characters (usual limit is 3). Since this index can only be used on
- # PostgreSQL, the 30 character limit for cross-database compatibility isn't
- # applicable.
- max_name_length = 31
-
-
- class BrinIndex(MaxLengthMixin, Index):
- suffix = 'brin'
-
- def __init__(self, *, pages_per_range=None, **kwargs):
- if pages_per_range is not None and pages_per_range <= 0:
- raise ValueError('pages_per_range must be None or a positive integer')
- self.pages_per_range = pages_per_range
- super().__init__(**kwargs)
-
- def deconstruct(self):
- path, args, kwargs = super().deconstruct()
- if self.pages_per_range is not None:
- kwargs['pages_per_range'] = self.pages_per_range
- return path, args, kwargs
-
- def create_sql(self, model, schema_editor, using=''):
- statement = super().create_sql(model, schema_editor, using=' USING brin')
- if self.pages_per_range is not None:
- statement.parts['extra'] = ' WITH (pages_per_range={})'.format(
- schema_editor.quote_value(self.pages_per_range)
- ) + statement.parts['extra']
- return statement
-
-
- class GinIndex(Index):
- suffix = 'gin'
-
- def __init__(self, *, fastupdate=None, gin_pending_list_limit=None, **kwargs):
- self.fastupdate = fastupdate
- self.gin_pending_list_limit = gin_pending_list_limit
- super().__init__(**kwargs)
-
- def deconstruct(self):
- path, args, kwargs = super().deconstruct()
- if self.fastupdate is not None:
- kwargs['fastupdate'] = self.fastupdate
- if self.gin_pending_list_limit is not None:
- kwargs['gin_pending_list_limit'] = self.gin_pending_list_limit
- return path, args, kwargs
-
- def create_sql(self, model, schema_editor, using=''):
- statement = super().create_sql(model, schema_editor, using=' USING gin')
- with_params = []
- if self.gin_pending_list_limit is not None:
- with_params.append('gin_pending_list_limit = %d' % self.gin_pending_list_limit)
- if self.fastupdate is not None:
- with_params.append('fastupdate = {}'.format('on' if self.fastupdate else 'off'))
- if with_params:
- statement.parts['extra'] = 'WITH ({}) {}'.format(', '.join(with_params), statement.parts['extra'])
- return statement
-
-
- class GistIndex(MaxLengthMixin, Index):
- suffix = 'gist'
-
- def __init__(self, *, buffering=None, fillfactor=None, **kwargs):
- self.buffering = buffering
- self.fillfactor = fillfactor
- super().__init__(**kwargs)
-
- def deconstruct(self):
- path, args, kwargs = super().deconstruct()
- if self.buffering is not None:
- kwargs['buffering'] = self.buffering
- if self.fillfactor is not None:
- kwargs['fillfactor'] = self.fillfactor
- return path, args, kwargs
-
- def create_sql(self, model, schema_editor):
- statement = super().create_sql(model, schema_editor, using=' USING gist')
- with_params = []
- if self.buffering is not None:
- with_params.append('buffering = {}'.format('on' if self.buffering else 'off'))
- if self.fillfactor is not None:
- with_params.append('fillfactor = %s' % self.fillfactor)
- if with_params:
- statement.parts['extra'] = 'WITH ({}) {}'.format(', '.join(with_params), statement.parts['extra'])
- return statement
|